SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '76881e90aabb0fb1086749d491b949d0d9d4179c5548cec9e2f9762f83236fc8' 
  AND token = 'V0IsSPlwwB3H1Yev9n4HXdwJmFqLFRYtAaDVqwf7LOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}